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Johann Vollmann Heinrich Grausgruber Helmut Wagentristl Heinrich Wohleser Pavel Michele 《Journal of the science of food and agriculture》2003,83(15):1581-1586
The presence of protease inhibitors in soybean prohibits the utilisation of the raw beans for food and feed. However, little information is available about environmental influences and the effects of nitrogen and sulphur supply on the antinutritional constituents of soybean. As these factors may influence protease inhibitors, soybean genotypes segregated according to the presence or absence of the Kunitz trypsin inhibitor have been evaluated for trypsin inhibitor activity (TIA) in field trials. TIA was affected significantly by environment (geographical location), fertilisation treatment and genotype. Environmental means of TIA were between 69.5 and 104.8 mg g?1. Nitrogen application, which caused an increase in seed protein content, resulted in a reduction in TIA by about 15% as compared with the control. Remarkably, simultaneous application of nitrogen and sulphur in the form of ammonium sulphate had a similar reductive effect on TIA to that of nitrogen application alone, although soybean protease inhibitors are rich in sulphur amino acids. Significant genetic variation in TIA was found both within the genotype class with the Kunitz inhibitor present as well as within the class lacking this inhibitor. The results suggest that TIA of soybean may be modified considerably by genetic improvement and appropriate agronomic management. Copyright © 2003 Society of Chemical Industry 相似文献
13.
The frequencies of multinational papers in various sciences 总被引:2,自引:1,他引:1
Helmut A. Abt 《Scientometrics》2007,72(1):105-115
Multinational papers are defined here as ones written by authors who reside in different countries during the course of research.
For each of 16 fields of science, I scanned the first 200 papers in 2005 in four major journals publishing original research
papers. Those journals produced 40% of all the citations among those journals with Impact Factors greater than 1.0. The frequencies
of multinational papers ranged from 13% in surgery to 55% in astronomy. Although one can list a dozen factors which might
contribute toward multinational papers, I lack the data to test most of those. There are only minor correlations with team
sizes and Impact Factors, inadequate to explain the range. There is a larger, but not convincing, dependence upon the fractions
of single-author papers and its cause, if real, is unclear. However, the most prominent factor seems to be the nature of the
objects studied; if they are usually local (e.g. in one hospital or in one laboratory), the papers tend to be domestic but
if most of the objects are available simultaneously to scientists in many countries (e.g. the sky in astronomy or the oceans
and the Earth’s atmosphere in geosciences or widespread diseases in the area of infectious diseases or plants and animals
widely distributed in biology), the papers are often international. Auxiliary results for 2005 are an average of 5.5 ± 0.3
authors per paper and 6.6 ± 1.0% one-author papers. 相似文献
14.
Modified (α‐diimine)nickel(II) catalysts are suitable for ethylene oligomerization reactions. Due to the mechanism (“chain running”), the formation of double‐bond isomers and branched olefins can be observed. The obtained oligomer mixtures show a Schulz–Flory distribution. Increasing ethylene pressure favors the selectivity of α‐olefin formation. The same effect can be observed when Lewis bases like thiophene or furane are added to the oligomerization reaction mixture. These results can be related to an interaction of the additives with the catalytic active species during the oligomerization process. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1356–1361, 2003 相似文献
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Helmut Richter Dr. rer. nat. Horst W. Tamler Dr. rer. nat. 《JOM Journal of the Minerals, Metals and Materials Society》1994,46(10):46-47
A new on-line texture-analyzing system and its application to nondestructive r value determination is discussed. In addition to providing a brief theoretical background and describing the instrumental set-up, the article presents off-line measurements with this equipment and demonstrates the high accuracy of the determined r-values. A special feature of the unit is the possibility to simultaneously measure the most important r values—r0, r45, r90, and rm. 相似文献
17.
This is a review of two electrical equivalent circuits for multi-element magnetostatic wave transducers. The two circuit models are identified as a transmission line and a two terminal model. Both models have been extended to all three principal MSW modes of propagation to the point where computer programs have been written to plot phase and amplitude response as measured by commercial network analyzers. A review is provided of the basic assumptions, similarities and differences, advantages and disadvantages, and limitations of the two models. The useful range of them covers many cases of practical interest in the one to twelve Ghz frequency range. 相似文献
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This paper reports on an evaluation of real-time properties of MAP (Manufacturing Automation Protocol) networks by analytical considerations and measurements. Based on a model of the time schedule of a communication cycle figures for response times (transport system) and message delays (MAC layer) are given. The influence of some options for handling acknowledgments within the transport layer is shown. The message delay at MAC layer is separated into an implementation-dependent and a protocol-dependent protion, and an upper bound is derived. Rules for selecting protocol parameters affecting real time behavior are given. Aspects for improved implementations of communication controllers for MAP networks are discussed. 相似文献
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